Engine low oil indicator



Sept l, 1953 R. N. ZIMMERMAN ENGINE Low OIL INDICATOR Filed Feb. 24, 1950 n @u R0 Om Qu 0 W 9 W Mw f I m M MU 1w JP ,g/ Z n M n 4. M 5a m 2 a v/ m 7 e N 3 e 3 b QW I 3 INI 2 ,WUU/ hm W I f i if m v a, 6/ 5 3 w f l g .9 6 0 0 H 6 i 7 A, 1. Pf i l, A, f I|Hw QW y O I IU W N 9 HW 41S 2 2 M 6M, 2 0 L 0 0l 0 l l l @Mw w .o9 -m e ,3/ l; I m s 2 l l I l l ll|||| m. (32. H/3 ,i m l//r 3 m Hl l I f l l I 4|, MW |1 f6 7 xll l we@ ow w 2 7 l 2 A, n m m n A, w 2

ATTEI RN EYE Patented Sept. 1, 1953 UNITED STATES PATENT OFFICE ENGINE LOW OIL INDICATOR Robert N. Zimmerman, Tucson, Ariz.

Application February 24, 1950, Serial No. 145,925 z claims. (o1. 20o-139) This invention relates to devices for indicating the oil level of internal combustion and other engines, and in particular the device relates to an engine oil protector or safety device including a small casing mounted in combination with an engine and having a thermostatic element in combination with a tube through which oil of the engine passes wherein with contact points for closing a circuit to a Warning light at a remote point positioned to be actuated by the thermostatic element the thermostatic element is actuated by heated oil passing through the tube to close the contacts to light the Warning light or provide a signal.

The purpose of this invention is to provide a device for providing a warning light when the oil of an engine is low to prevent burning out bearings and the like.

Numerous engines are operated when the oil is dangerously low because means is not provided that operate automatically to warn the operator of the engine that the oil is substantially exhausted. With this thought in mind this invention contemplates a comparatively small unit mounted on or in combination with an engine in which a, thermostatic element in the unit is iniluenced by heated oil passing through a, tube extended through the unit and the thermostatic element closes a circuit to light a warning signal lamp or actuate a warning device when the temperature of the oil passing through the unit reaches a predetermined degree.

The object of this invention is, therefore, to provide means for forming a small unit that may be mounted in combination with an engine and that is actuated to provide a safety or warning signal when the oil of an engine is too low for safe or eficient operation of the engine,

Another object of the invention is to provide a low oil warning device that may be mounted in combination with engines now in use without changing the engine or parts thereof.

A further object of the invention is to provide a low oil Warning device for engines of the internal combustion and other types which is of a simple and economical construction.

With these and other features and advantages in view the invention embodies a casing having a tube extended therethrough with a thermostatic element and a contact point mounted therein whereby with the contact point connected to a signal the thermostatic element completes a circuit to actuate the signal when the temperature of fluid passing through the tube reaches a. predetermined degree.

Other features and advantages of the invention will appear from the following description taken in connection with the drawing wherein:

Figure 1 is a front elevation of the engine oil protector.

Figure 2 is a rear elevational view of the casing of the protector with the mounting plate omitted.

Figure 3 is a vertical section through the device taken on line 3 3 of Figure l.

Figure 4 is a cross section through the device taken on line 4-4 of Figure 1.

Figure 5 is a detail illustrating the mounting of the thermostatic element in the casing through which the position of the element is adjustable to regulate the temperature at which the device operates.

Referring now to the drawing wherein like reference characters denote corresponding parts the engine low oil detector of this invention includes a casing l0, a tube Il extended through the casing, a thermostatic element l2, a contact I3, and a signal light I4.

In the design shown, the casing l0 is rectangular shaped having an outer or front wall E5 in which the thermostatic element is mounted by a stud I6, and the casing is attached to a mounting plate I7 by screws I8 and i9 that extend through flanges 2D and 2l, respectively. The flanges are provided with bolt holes 22 and 23, respectively, through which the screws extend.

The casing l0 is provided with an upper wall 23 and a lower wall 24 and the tube Il extends through the walls 23 and 24 and is secured in position by welding as indicated at the points 25 and 26. The ends of the tube il are provided with threaded nipples 21 and 2,8 on which coupling members 29 and 30, respectively, are threaded, and, the coupling members connect oil tubes 3| and 32 to the ends of the tube il.

In the design shown the thermostatic element l 2 is in the form of a spiral with a straight inner end 33 extended through a slot 34 in the stud l and the outer coil of the element is provided with an end 35 that is positioned to engage the contact I3, as shown in Figure 2. rlhe contact i3 is mounted in a ange 36 of a clamp 3l that is adjustably mounted on the inner surface of the outer wall l5 of the casing by a bolt 38. The contact I3 is insulated from the flange 36 by a bushing 39 and with the thermostatic element l2 grounded through the casing a circuit may be completed from a suitable source of current supply from the point I3 through the end 35 with the end in engagement with the contact and through the wire 40 to the light Ill'. The thermostatic element is influenced by the heat to expand until the end 35 engages a contact i3.

The stud i6 is provided with a threaded stem 4i that extends through an opening 42 in the front Wall i5 of the casing and a nut 43 on the stem 4i clamps a shoulder 44 against the inner surface of a Wall l5. The outer end of the stem 4i is provided with a winding or turning key or pin 45, by which the stud may be rotated to adjust the position of the end 35 on the inside of the casing. The outer face of the casing may be provided with a scale 46 for indicating the position of the end 35 of the thermostatic element in relation to the Contact I3.

A gasket 47 is provided between the inner face of the casing i0 and the anges thereof and the mounting plate H. The mounting plate i7 is provided with bolt holes 48 by which the casing may be mounted on or in combination with an engine housing.

It will be understood that modications may be made in the design and arrangement of the parts Without departing from the spirit of the invention.

What is claimed is:

1. An engine low oil indicator for the oil circulation system of an engine comprising a tube connected in theA oil circulating system of the engine, a stud mounted adjacent said tube, means on said stud for adjusting said stud, a thermostatic; bimetallic element connected at one end to said stud and having a contact on the opposite end thereof positioned to be inuenced by heat of the tube, a second Contact adapted to be engaged by the end of the contact at the opposite end of the thermostatic element, and means for adjusting the position of the said second contact in relation to the contact on the thermostatic element.

2. In an engine 10W oil indicator, the combination which comprises a rectangular shaped casing, a tube extending longitudinally through said casing, a spiral birnetallic thermostatic element having a stud on one end Which is adjustably mounted in the casing and having an opposite extended end, a Contact adjustably mounted in the casing and adapted to be engaged by the extended end of the thermostatic element, and means mounted on the stud for indicating the position of the extended end of the thermostatc element from the exterior of the casing.

ROBERT N. ZIMMERMAN.

References Cited in the file, 0f this patent `(.T1.\I'EDY STATES PATENTS Number Name Date 186,553 Frost Jan. 23, 1877 648,543, Wilke May 1, 1900 783,376 Howe Feb. l2l, 1905 1,931,238- Phelan Oct. 17', 1933 1,942,697 Henning Jan. 9, 1934 2,273,381 Shaw Feb. 17, 1942 

